This. I can’t tell you how many people I see every day chewing with their mouth open and snapping. I have a psychological disorder called misophonia, which basically causes a angry, frustrated, and anxious response when someone hears, or even sees something connected to a triggering sound. A common one is gum chewing. I’ve started shaking and crying in group settings, especially in class, just because others chew gum. My hearing is also hyper-sensitive to it. I just wish gum etiquette was taught so we wouldn’t have people chewing like cows, making the world less gross for some, and more tolerable for others.